Sea Tel 9497B-1, Инструкция по установке и эксплуатации

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Maintenance and Troubleshooting 9497B-1 C/Ku-Band TVRO
7-10
input is corrupt, not stable or not consistently accurate the tracking errors will become large enough to cause
the antenna to be mis-pointed off satellite.
Satellite Reference Mode will uncouple the gyro reference from the azimuth rate sensor control loop. This
decoupling of the Gyro source only happens 5 minutes after an azimuth command has been sent to the
antenna by means of an AZ target command, a search pattern initiated, or the a Satellites longitudinal
position is targeted. When operating in Satellite Reference Mode changes in ships gyro reading will reflect its
changes to the ACU’s display but will not directly affect the azimuth control loop. The Pedestal Control Unit
will stabilize the antenna based entirely on the azimuth rate sensor loop and the tracking information from
DishScan. This will keep the azimuth rate sensor position from eventually drifting away at a rate faster than
the tracking loop can correct by using the tracking errors to regulate the rate sensor bias.
Satellite Reference Mode can be used as a diagnostic mode to determine if tracking errors are caused by
faulty gyro inputs.
Satellite Reference Mode
MUST be used when:
•
No Gyro Compass is available
•
Frequent or constant ACU Error Code 0001 (Gyro Compass has failed)
•
Gyro Compass output is NMEA heading
•
Flux Gate Compass is being used
•
GPS Satellite Compass is being used
To view, or change, the Satellite Reference Mode status, select the SAT REF remote parameter:
1.
Press the RIGHT arrow, then press the UP arrow and last press the ENTER key to turn Satellite
Reference Mode ON.
2.
Press the RIGHT arrow, then press the DOWN arrow and last press the ENTER key to turn Satellite
Reference Mode OFF.
If you change this remote parameter, you must save the change using REMOTE PARAMETERS.
7.3.11.
An Error Code 8 as reported by the ACU is an indication that the above decks equipment has experienced an
error. One of the functions available within the “
Comm Diagnostics
” tool window provides the means to
read and decode the actual discreet Pedestal Function Error.
To Read/Decode an ACU Error Code 0008 (Pedestal Function Error):
1. Select the
“Comm
Diagnostics”
window
under to the Tools
submenu or Press “CTRL +
C”